import java.security.Key;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

public class MY {
    public static void main(String[] args) {
        int[] arr = new int[100000];
        Map<Integer,Integer> hashMap= new HashMap<>();

    }
    public static void main1(String[] args) {
        //删除字符串str与字符串str1相同的字符
        ArrayList<Character> list = new ArrayList<>();
        String str = "welcome to beijing";
        String str1 = "come";
        for (int i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            if(! str1.contains(ch+"") ){
                list.add(ch);
            }
        }
        for (Character x: list) {
            System.out.print(x);
        }
    }
}
